This application relates to a method of inspecting whether a surface of a component needs repair by imprinting the surface onto a marking media.
Gas turbine engines are known and typically include a fan delivering air into a bypass duct as bypass air and further into a compressor. Air in the compressor is compressed and then delivered into a combustor where it is mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors driving them to rotate. It is desirable to maintain tight clearances between a radially outer portion of blades rotating with both the compressor and turbine rotors and outer housings or static structure.
Thus, it is known to put an abradable seal radially outwardly of the blades in a compressor and turbine section. The outer tips of the blades may be provided with an abrasive surface to wear into the abradable seal. In particular, abrasive surfaces are applied to the radially outer portion of the compressor blades.
The abrasive surfaces wear and eventually need to be recoated. This is a procedure that would desirably be limited as it will typically require removal of the blade, and the abrasive coatings themselves are expensive. Still, the abrasive materials are recoated periodically, without regard to actual need.